Urothelial carcinoma after external beam radiation therapy for prostate cancer

We reviewed the clinical course of patients in whom urothelial carcinoma developed following radiation therapy for prostate cancer.

A retrospective review of all patients between 1990 and 2005 with the diagnosis of bladder and prostate cancer was performed. Of 125 total patients new onset urothelial carcinoma developed in 11 after undergoing external beam radiation therapy for prostate cancer.

Whole pelvis external beam radiation therapy with a proton boost to the prostate was the radiation modality in 7 of the 11 patients (64%), while the remaining 4 patients received standard external beam radiation only. Urothelial carcinoma was detected a mean of 3.07 years after completion of radiation therapy in the proton group, compared to a mean latency period of 5.75 years in the standard radiation group (p = 0.09). Average patient age at diagnosis was 72 years (range 64 to 84). All patients presented with gross hematuria and had cystoscopic findings of coexisting radiation cystitis. Of the 11 patients 5 (45%) presented with grade 3 carcinoma and eventually 7 (64%) required radical cystectomy. Urothelial tumors with sarcomatoid features (carcinosarcoma and spindle cell sarcomatoid) developed in 2 patients (18%). Of the 11 patients 10 (91%) were nonsmokers at the time of urothelial carcinoma diagnosis.

Urothelial carcinoma in patients with previous radiation therapy for prostate cancer is often high grade, and the majority of patients have cancer progression requiring cystectomy. A high incidence of urothelial carcinoma with sarcomatoid features was seen in these patients.